1. Field of the Invention
The present invention relates to a method for manufacturing a phosphor screen which is suitable for making a color cathode ray tube having a face plate of, for example, flat plate-shape and to a photo-sensitive phosphor paste which is used to carry out the above manufacturing method of the cathode ray tube.
2. Description of the Prior Art
Recently, a requirement for a cathode ray tube which has a phosphor screen coated on a plate glass of perfectly flat plate-shape is increased. Such cathode ray tube has already been put into practical use as a monochromatic tube which is used as a projector or the like. One of the features of such cathode ray tube is as follows: Since an image is displayed on a perfectly flat plate glass, the image is free from an optical distortion and this cathode ray tube is very suited for a display apparatus of high efficiency and so on. For this reason, such a cathode ray tube is naturally desired as a color cathode ray tube.
The cathode ray tube in which the phosphor screen is formed on the plate glass of flat plate-shape has no skirt portion unlike a prior art panel, so if the phosphor screen thereof is formed by the prior art manufacturing method, i.e., a so-called slurry method, much phosphor slurry will be lost unnecessarily, while when a stripe and so on are printed on the flat glass plate by a photographic technique, slurry will adhere to a reference plane portion. Therefore, it has been considered to employ the screen printing method. In this case, however, since the screen printing method is low in accuracy, it is almost impossible to directly print the phosphor stripe which needs accuracy of micron order.